Apparatus for and a method of joining the edges of two sheet portions together

ABSTRACT

Two abutting edges of two sheets, or one sheet where, for example, a tubular member is to be formed, each has an edge portion formed in a U-shaped section so that the edges can be placed end on with the U-shape of one 90* out of alignment with and enclosed within the U-shape of the other. These U-shaped sections enclosed one within the other are fed successively to four pair of rotatable profiled deforming rollers which successively fold the arms and bases of the U-shaped sections over one another to produce a joint between the sheets, or on the sheet, in which the base and arm positions of one &#39;&#39;U&#39;&#39; are aligned with one arm and the base portion of the other &#39;&#39;U&#39;&#39;.

United States Patent 1191 1111 3,838,498 Lipp 1 Oct. 1, 1974 APPARATUS FOR AND A METHOD OF 3,407,640 10/1968 Lipp 113/54 JOINING THE EDGES o wo SHEET lilkarris om son PORTIONS TOGETHER 3,773,005 11/1973 Day eFal. 113/55 [75] Inventor. Xaver Llpp, Tannhausen, Germany FOREIGN PATENTS OR APPLICATIONS 1 Assignee! Silo Verfahrens AG, 81 899,446 6/1962 Great Britain 113 55 Switzerland 22 Filed; 1 1973 Primary ExaminerCharles W. Lanham Assistant Examiner-James R. Duzan [21] Appl' 333,291 Attorney, Agent, or Firm-Roylance, Abrams, Berdo & Kaul [30] Foreign Application Priority Data Mar. 2, 1972 Germany 2210055 ABSTRACT Two abutting edges of two sheets, or one sheet where, U-S- for example a tubular member is to be formed, eaeh ll'ilt. has an edge portion formed in a U- haped section so Fleld of Search l 55, 56, 57, that the edges can be placed end on the U-Sha pe 29/509; 72/511 52 of one 90 out of alignment with and enclosed within the U-shape of the other. These U-shaped sections enl References Cited closed one within the other are fed successively to UNITED STATES PATENTS four pair of rotatable profiled deforming rollers which 1,976,148 10/1934 Sonntag 113 55 successively fold the arms and bases of the p 2,171,297 8/1939 211111161 et 61. 113/55 sections over one another to produce a joint between 2,275,629 3/1942 Ingles 113/54 the sheets, or on the sheet, in which the base and arm 2,436,383 2/1948 Dettman 113/54 positions of one U are aligned with one arm and the 2,682,850 7/l954 Close 113/54 base portion of the other U 2,950,697 8/1960 Flagler 113/54 3,346,941 10/1967 Patry 61 a1. 113/54 8 Claims, 6 Drawing Figures 7 iii. .1lii

APPARATUS FOR AND A METHOD OF JOINING THE EDGES OF TWO SHEET PORTIONS TOGETHER The present invention relates to apparatus for and a method joining together adjacent sheet portions.

The invention is particularly concerned with the joining of plastically deformable metal sheet, in which one of the edges has two spaced bends each of about 90 and each made in the same direction, and the other edge additionally has an approximately 90 bend made in the opposite direction and situated farther away from the end of the plate, so that the edges are each formed with a U-shaped section.

When two abutting edges are connected by folding, it has been found that when the previously bent arm of one U is folded over the arm of the U, the first arm springs back after the folding operation during which the fold should be compressed, and at least obstructs the compression of the fold. It was therefore necessary to include an additional operation to bring the first arm into a position in which it cannot obstruct the next operation by springing back.

The object of this invention is to eliminate this additional operation so that there is no need to carry out any action on the first arm to obviate the springing back thereof.

According to one aspect of the present invention, there is provided apparatus for connecting together two abutting sheet portions each of which is formed at its edge with a substantially U-shaped section, comprising means adapted to receive the portions with one U- shaped section enclosed within and substantially at right angles to the other U-shaped section, first deforming means for deforming one arm of said other U- shaped section over one arm of said one U-shaped section, said first deforming means comprising two deforming members one of which includes a groove with an inclined side operative to carry out said aforementioned arm deforming action, and second deforming 'means, to which the sheet portions pass after said first performing means, comprising two deforming members one of 'which includes a groove and the other of which includes a wedge shaped projection aligned with the groove, said second deforming means being operative to deform the other arm of the enclosing U-shaped section and the base of the enclosed U-shaped section so as to reduce the angle between this arm and base and the enclosed arm of the enclosed U-shaped section while simultaneously aligning the enclosed and enclosing arms.

According to another aspect of the invention there is provided a method of connecting together two abutting sheet portions each of which is formed at its edge of a U-shaped section and with the U-shaped section of one portion enclosed with and substantially at right angles to the other U-shaped section including the steps of feeding the sheet portions to first deforming means, deforming an arm of the enclosing U-shaped section over an arm of the enclosed U-shaped section, feeding the thus deformed sheet portions to second deforming means deforming the other arm of the enclosing U- shaped section and the base of the enclosed U-shaped section so as to reduce the angle between this arm and base and the enclosed arm of the enclosed U-shaped section while simultaneously aligning the enclosed and enclosing arms.

In order that the invention will be more clearly understood, one embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing in which,

FIG. 1 is a side elevation of one embodiment of apparatus for forming together two sheet portions,

FIG. 2 shows the edges of the two sheets in the starting conditions first before entering the apparatus of FIG. 1;

FIG. 3 is a section on the line IIIIII of FIG. 1 with inserted sheets prepared in accordance with FIG. 2;

FIG. 4 to FIG. 6 are respectively sections on the lines IVIV, V--V and VIVI in FIG. 1 showing the formation of the sheets on those sections.

Referring to the drawings, four pairs of rollers 2 9 are mounted in a frame 1 so as to be vertically adjustable and rotatable. The two rollers of each pair are positively connected to each other by gearwheels. One roller of each pair is adapted to be driven from the adjacent pair by means of a chain, each chain connecting only two adjacent pairs of rollers. One of the gearwheels connected to the rollers 2 9 so as to rotate therewith is connected to a drive motor so as to be driven therefrom. The rollers 2 9 are thus each adapted to be driven at the same speeds.

Referring to FIG. 2, which shows a cross-section of two metal sheets 11 and 12, which are to be connected together, the sheet 11 has three bends l3 15, each made through an angle of 90, the bends 14 and 15 being made in the same direction and the bend 13 being made in the opposite direction thereto. The sheet 12 has two bends l6 and 17 each made through 90 in the same direction. The bends 13, 14 and 16, 17 and preferably also l4, 15 are equidistant from one another. The free ends of the sheets 11 and 12 bear the references 18 and 19 and the zones between the bends bear the references 21, 22 and 23 respectively. Thus, 22 and 23 are first zones in metal sheets 11 and 12, respectively, and 21 is a second zone in metal sheet 12. The lengths of the free ends are somewhat shorterthan the distances between the bends 13,14, 16,17 and 14,15 respectively. By bending the sheets in this way, the edge portion of each sheet is formed with a U- shaped section. In the case of sheet 12, however, the upright axis of the U is parallel to the plane of the sheet; whereas in the case of sheet 11 the upright axis of the U is perpendicular to the plane of the sheet 11. With the exception of the bends, the sheets 11 and 12 may be flat or be bent about an axis extending in parallel relationship to the bends. Alternatively, the sheets 11, 12 having the bends l3 17 may be bent about an axis at right angles to the zones 21 and 23 in FIG. 2 during the folding together of their edges 19, 21, 22 and 18, 23 as shown in FIGS. 3 6. In a finished tube, the finished fold may therefore extend in parallel relationship to the tube longitudinal axis, in the form of a ring around its periphery, or in the form of a spiral or helix on its periphery.

The free end 19 is bent through an angle of between 15 and more particularly between 30 and 60, by means of the rollers 2, 3. To this end, the roller 3 has an annular groove 27 which is disposed between two flanges and which has an inclined wall 28 and a wall 29 extending at right angles to the axis of rotation. The roller 2 is of cylindrical construction.

During the next operation, as shown in FIG. 4, the free end 19 is applied against the free end 18 and the zones 21, 23 are simultaneously bent through an angle of between and 75, more particularly between and 60, in the direction of the sheet 11. To this end, the roller 4 has an annular groove 30 with an inclined wall 31 and with a wall 32 extending at right angles to the axis of rotation, the wall 31 abutting the zone 21 and the wall 32 abutting the zone 22.

The roller 5 has an annular projection 33, the inclined surface 34 of which abuts the zone 23 and the wall of which at right angles to the axis abuts the free end 19. The rollers 4 and 5 also have'fianges 36 and 37, of which the flange 36 has the wall 32 abutting the zone 22 and bounding the annular groove 30.

As a result of the bending of the zone 23, the free end 19 engages in an acute angle and is therefore prevented from springing back. The wall 32 also ensures that when the free end 19 is bent in by the roller 5 the zone 22 is not pressed in the direction of the roller 4.

The pair of rollers 6, 7 serves to place the free ends 18, 19 in parallel relationship and the zone 22 in parallel relationship to the zones 21 and 23, and to apply the free end 19 against the zone 23. To this end, the roller 6 has. an annular groove 41 which has an inclined wall 42 and the roller 7 has an annular bead 43 which cooperates with the annular groove il and which has a corresponding inclined wall 44. The rollers 6 and 7 also have annular flanges 45 and 46.

In the next operation, the cylindrical rollers 8 and 9 cause the fold to be disposed at right angles to the sheets 11 and 12.

While the annular groove 27 of the roller 3 is situated on one side of the parts 18, 19, 21, 22,23 being processed, the annular grooves 30 and 41 of the rollers 4 and 6 are situated on the other side.

lnstead of the rollers, stamping tools or the like may be used as described above to form the sheet-metal edges. If only stamping tools are used for forming the sheet-metal edges, feed rolls are additionally required.

What is claimed is:

1. An apparatus for connecting the abutting edges of first and second sheet metal parts, each part having two initial substantially 90 bends in the same direction to form U-shaped channels, the first of said bends being adjacent the edge to define a free end, the second of said bends being adjacent the first bend to define a first zone, said first sheet metal part having a third substantially 90 bend in a direction opposite said first two bends to define a second zone between said first zone and said sheet portion of said first part, the axes of all bends being parallel to the abutting edges of said first and second parts, wherein all zones are substantially equal in width and said free ends on the two parts are equal to each other in width but shorter than said zone portions, and wherein the U-shaped channel of said second part is located inside the U-shaped channel of said first part, the apparatus comprising:

first deformation means for increasing the angle of said first bend which defines the free end portion of said first part so that said free end portion occupies a new position substantially midway between the original 90 position and the plane occupied by the free end portion of said second part;

second deformation means for increasing all three of said bends in said first part and the free end bend of said second part while decreasing the bend between the first zone and the sheet portion of said second part wherein all of said bends formed by said second deformation means are formed simul taneously; and I third deformation means for further increasing said first and second bends of said first part and said second bend of said second part from said bends formed by said second deformation means to bends of substantially 180 where by said free end and said first and second zones of said first part and said free end and said first zone of said second part are all substantially parallel so that the first, second and third deformation means prevent the free end portion of said first part from interfering with the formation of a solid connection of the abutting edges of said first and second sheet metal parts.

2. An apparatus according to claim 1 further comprising: fourth deformation means for decreasing the bend between the second zone and the sheet metal portion of said first part while simultaneously increasing the bend between the first zone and the sheet metal portion of said second part thus making the free end and first and second zones of said first part, and the free end and first zones of said second part, perpendicular to said first and second sheet metal parts.

3. An apparatus according to claim 2 wherein said first, second, third and fourth deformation means each comprise pairs of rollers, the two rollers of each of said pairs having axes which are parallel to each other and wherein the adjacent cylindrical peripheral surfaces of the two rollers of eachof said first, second, third and fourth deformation means are shaped to increase and decrease the initial bends of each of said first and second sheet metal parts.

4. An apparatus according to claim 3 wherein said first roller of said first deformation means has at least a portionof said peripheral surface inclined with respect to the axis of said roller to form an angle in the range of 30 to 60, said inclined peripheral surface being operative to increase the angle of said first bend which defines the free end portion of said first part so that said free end portion occupies a new position substantially midway between the position and the plane occupied by the free end portion of said second part.

5. An apparatus according to claim 3 wherein one roller of said pair of rollers comprising said pair of rollers comprising said second deformation means includes a first projection extending around the cylindrical peripheral surface of said one roller, and wherein a groove is defined between said first projection and a second projection extending around the cylindrical surface of said one roller, said second projection having an inclined surface on the groove side thereof; wherein said other roller of said pair of rollers comprising said second deformation means includes rectangular and wedge shaped projections extending around the cylindrical peripheral surface of said other roller to form a groove defined between said rectangular and wedge shaped projections; and wherein said wedge shaped projection of said other roller extends into said groove of said one roller, said wedge shaped projection being spaced apart from said inclined surface of said second projection of said one roller to accommodate the sheet material of said first and second parts.

6. A method of connecting the abutting edges of first and second sheet metal parts, each part having two initial substantially 90 bends in the same direction to form U-shaped channels, the first of said bends being adjacent the edge to define a free end, the second of said bend being adjacent the first bend to define a first zone, said first sheet metal part having a third substantially 90 bend in a direction opposite said first two bends to define a second zone between said first zone and said sheet portion of said first part, the axes of all bends being parallel to the abutting edges of said first and second parts, wherein all zones are substantially equal in width and said free ends on the two parts are equal to each other in width but shorter than said zone portions, and wherein the U-shaped channel of said second part is located inside the U-shaped channel of said first part, comprising the steps of:

increasing the angle of said first bend which defines the free end portion of said first part to a position in which the free end portion occupies a new position between the original 90 position and the plane occupied by the free end portion of said second the free end and first zone of the second part are all substantially parallel, thus preventing the free end portion of the first part from interfering with the formation of a solid connection of the abutting l 5 edges of the first and second sheet metal parts.

7. The method of claim 6 wherein the angle formed in said step of increasing said first bend is in the range of to 80.

8. The method of claim 6 wherein the increased bends formed in the step of simultaneously increasing all three bends are in a range of from 15 to 75 

1. An apparatus for connecting the abutting edges of first and second sheet metal parts, each part having two initial substantially 90* bends in the same direction to form U-shaped channels, the first of said bends being adjacent the edge to define a free end, the second of said bends being adjacent the first bend to define a first zone, said first sheet metal part having a third substantially 90* bend in a direction opposite said first two bends to define a second zone between said first zone and said sheet portion of said first part, the axes of all bends being parallel to the abutting edges of said first and second parts, wherein all zones are substantially equal in width and said free ends on the two parts are equal to each other in width but shorter than said zone portions, and wherein the Ushaped channel of said second part is located inside the U-shaped channel of said first part, the apparatus comprising: first deformation means for increasing the angle of said first bend which defines the free end portion of said first part so that said free end portion occupies a new position substantially midway between the original 90* position and the plane occupied by the free end portion of said second part; second deformation means for increasing all three of said bends in said first part and the free end bend of said second part while decreasing the bend between the first zone and the sheet portion of said second part wherein all of said bends formed by said seconD deformation means are formed simultaneously; and third deformation means for further increasing said first and second bends of said first part and said second bend of said second part from said bends formed by said second deformation means to bends of substantially 180* whereby said free end and said first and second zones of said first part and said free end and said first zone of said second part are all substantially parallel so that the first, second and third deformation means prevent the free end portion of said first part from interfering with the formation of a solid connection of the abutting edges of said first and second sheet metal parts.
 2. An apparatus according to claim 1 further comprising: fourth deformation means for decreasing the bend between the second zone and the sheet metal portion of said first part while simultaneously increasing the bend between the first zone and the sheet metal portion of said second part thus making the free end and first and second zones of said first part, and the free end and first zones of said second part, perpendicular to said first and second sheet metal parts.
 3. An apparatus according to claim 2 wherein said first, second, third and fourth deformation means each comprise pairs of rollers, the two rollers of each of said pairs having axes which are parallel to each other and wherein the adjacent cylindrical peripheral surfaces of the two rollers of each of said first, second, third and fourth deformation means are shaped to increase and decrease the initial bends of each of said first and second sheet metal parts.
 4. An apparatus according to claim 3 wherein said first roller of said first deformation means has at least a portion of said peripheral surface inclined with respect to the axis of said roller to form an angle in the range of 30* to 60*, said inclined peripheral surface being operative to increase the angle of said first bend which defines the free end portion of said first part so that said free end portion occupies a new position substantially midway between the 90* position and the plane occupied by the free end portion of said second part.
 5. An apparatus according to claim 3 wherein one roller of said pair of rollers comprising said pair of rollers comprising said second deformation means includes a first projection extending around the cylindrical peripheral surface of said one roller, and wherein a groove is defined between said first projection and a second projection extending around the cylindrical surface of said one roller, said second projection having an inclined surface on the groove side thereof; wherein said other roller of said pair of rollers comprising said second deformation means includes rectangular and wedge shaped projections extending around the cylindrical peripheral surface of said other roller to form a groove defined between said rectangular and wedge shaped projections; and wherein said wedge shaped projection of said other roller extends into said groove of said one roller, said wedge shaped projection being spaced apart from said inclined surface of said second projection of said one roller to accommodate the sheet material of said first and second parts.
 6. A method of connecting the abutting edges of first and second sheet metal parts, each part having two initial substantially 90* bends in the same direction to form U-shaped channels, the first of said bends being adjacent the edge to define a free end, the second of said bend being adjacent the first bend to define a first zone, said first sheet metal part having a third substantially 90* bend in a direction opposite said first two bends to define a second zone between said first zone and said sheet portion of said first part, the axes of all bends being parallel to the abutting edges of said first and second parts, wherein all zones are substantially equal in width and said free ends on the two parts are equal to each other in wIdth but shorter than said zone portions, and wherein the U-shaped channel of said second part is located inside the U-shaped channel of said first part, comprising the steps of: increasing the angle of said first bend which defines the free end portion of said first part to a position in which the free end portion occupies a new position between the original 90* position and the plane occupied by the free end portion of said second part; simultaneously increasing all three of the bends in the first part and the free end bend of the second part while decreasing the bend between the first zone and the sheet portion of the second part; and further increasing the first and second bends of the first part and the second bend of the second part to bends of substantially 180* whereby the free end and the first and second zones of the first part and the free end and first zone of the second part are all substantially parallel, thus preventing the free end portion of the first part from interfering with the formation of a solid connection of the abutting edges of the first and second sheet metal parts.
 7. The method of claim 6 wherein the angle formed in said step of increasing said first bend is in the range of 15* to 80*.
 8. The method of claim 6 wherein the increased bends formed in the step of simultaneously increasing all three bends are in a range of from 15* to 75 *. 